BISC 207: 7.1, 7.5, 7.6, 8.1, 8.2, 8.3

Cellular respiration

Process where chemical energy in organic molecules is converted to ATP.

Photosynthesis

light energy is converted into chemical energy (found in glucose)

redox chemistry

the transfer of electrons from one reactant to another

The movement of electrons releases energy from organic compounds

This is the energy we use to synthesize ATP

OIL RIG (Oxidation Is Loss: Reduction is Gain)

oxidation

loss of electrons from one reactant

reduction

gain of electrons by one reactant

electron shuttles

temporarily hold onto high-energy electrons so they can be transferred from reactants to products

Cellular respiration-NADH and FADH2

Photosynthesis-NADPH

Aerobic respiration

Process consuming oxygen and releasing carbon dioxide via organic molecule oxidation.

--breathing

Glycolysis

Metabolizes glucose into two pyruvate molecules, yielding two ATP and two NADH.

--cytoplasm

Pyruvate oxidation

The breakdown of pyruvate to release an acetyl group.

2NAD+ → 2NADH

--matrix

Citric acid cycle

Metabolic cycle central to cellular respiration occurring in the mitochondria.

--matrix

—2 acetyl CoA molecules are consumed

—6 NAD+ → 6NADH

—2FAD → 2FADH2

—2ADP → 2ATP

Oxidative phosphorylation

Process where NADH and FADH2 are oxidized to make ATP via ADP phosphorylation.

--matrix

Electron Transport Chain

A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.

respiratory chain

a series of membrane associated electron carriers

the oxygen we breathe is used in this process

H+ electrochemical gradient

the concentration of H+ is higher outside of the matrix than inside and an excess of positive charge exists outside the matrix

ATP synthase

Protein complex acting as a rotary machine that synthesizes ATP using an H+ gradient.

The H+ electrochemical gradient==potential energy

flow of H+ back into the matrix==exergonic process-free energy released is used to synthesize ATP from ADP and P

Rotary machine that makes ATP as it spins

Rotation is caused by movement of H+ ions

H+ electrochemical gradient

Higher H+ concentration outside the mitochondrial matrix storing potential energy.

Photosynthesis

Process converting light energy into chemical energy in glucose, producing oxygen.

Calvin cycle

Metabolic cycle driven by NADPH and energy to fix carbon into sugars.

chloroplasts

organelles found in plant and algal cells that carry out photosynthesis

Chlorophyll

Pigment found in chloroplasts that gives plants their green color.

mesophyll

the tissue in the internal part of the leaf, contains cells with chloroplasts

These cells must receive light and also obtain water and carbon dioxide

Stomata

Pores in plant leaves through which gases like oxygen exit.

thylakoid membrane

third membrane that contains pigment molecules, including chlorophyll

--includes thylakoids, granum, and stroma

NADPH

Electron carrier providing energy and electrons to drive the Calvin cycle.

wavelength

the distance between the peaks in a wave pattern

electromagnetic spectrum

encompasses all possible wavelengths of electromagnetic radiation

photons

massless particles traveling in a wavelike pattern and moving at the speed of light-each photon contains a specific amount of energy

pigment

a molecule that can absorb light energy-when light strikes a pigment, some of the wavelengths of light energy are absorbed, whereas others are reflected

light energy

the visible spectrum can be absorbed by an atom when it boosts an electron to a higher energy level-an unstable condition

electron stability

An excited electron may drop down to a lower energy level and release heat

Releasing energy in the form of light

Resonance energy transfer-an excited electron can transfer its extra energy to an electron in a nearby molecule

An excited electron is removed from the molecule in which it is unstable and transferred to another molecule where it is stable

chlorophyll a

A photosynthetic pigment that participates directly in the light reactions, which convert solar energy to chemical energy.

chlorophyll b

An accessory photosynthetic pigment that transfers energy to chlorophyll a.

carotenoids

type of pigment that can absorb light and facilitate photosynthesis in chloroplasts

Impart a color that ranges from yellow to orange to red

Often the major pigments in flowers and fruits

absorption spectrum

a graph that plots a pigment’s light absorption as a function of the light’s wavelength 

action spectrum

plots the rate of photosynthesis as a function of the wavelength of light

The highest rates of photosynthesis in green plants correlate with the wavelengths that are strongly absorbed by the chlorophylls and carotenoids

Photosystem I (PSI)

Photosystem that transfers high-energy electrons to reduce NADP+ into NADPH.

Photosystem II (PSII)

Initial photosynthesis step that oxidizes water to replenish excited electrons.

Light harvesting complex

Antenna complex of chlorophylls that directly absorbs photons of light.

Primary electron acceptor

Molecule accepting high-energy electrons from excited pigment molecules.

Substrate-level phosphorylation

Direct transfer of a phosphate group from a molecule to ADP.

Photoautotrophs

Organisms using light energy to make organic molecules from inorganic sources.

Thylakoids

Flattened, fluid-filled tubules formed by the thylakoid membrane inside chloroplasts.

Granum

A stack of thylakoid membranes inside a chloroplast.

Stroma

The fluid-filled region of the chloroplast surrounding the thylakoid membrane.

Resonance energy transfer

Process where an excited electron transfers extra energy to a nearby molecule.

Linear electron flow

Combined movement of electrons from PSII to PSI reducing NADP+ to NADPH.

OIL RIG in redox reactions

Oxidation Is Loss of electrons, Reduction Is Gain of electrons.